In my Windows Vista setup, I can just press fn-F5 on my laptop to toggle screen display and output to a projector or external monitor.

After I switched to Ubuntu, the hot key is no longer working.

With a little research, I found that the problem lies with my xorg.conf file. It is configured to have only one output device.

I decided to test out a bit and “clone” the laptop screen to the VGA port and it works!

Here is what I did:

sudo gedit /etc/X11/xorg.conf

Look for the section
Section “Device”
Identifier “Intel Corporation Mobile 945GM/GMS/940GML Express Integrated Graphics Controller”
Driver “i810″
BusID “PCI:0:2:0″
EndSection

Insert the code:

Option “MonitorLayout” “CRT,LFP”
Option “Clone” “true”
Option “DevicePresence” “true

before the EndSection

Save the file and exit.

Press “Ctrl + Alt + Backspace” to restart Xorg.conf

That’s it! You can now see your screen on the projector or external monitor.